It may be different reasons why this error could occur. In general the problem is that Xtraction relies on Internet Information Services (IIS), and some of the Xtraction application pools is in stopped state.
Recycling IIS could resolve the issue temporarily. To find the reason why the Xtraction application pool is stopping, it is recommended to review the Windows Event Viewer logs.
For example, check if there is any lack of memory at the server, if there is any other CA product installed at the same server causing RAM memory consumption which could be impacting on the Xtraction application activity.